Abstract:The utility and appropriateness of PN-EN 1992-3 [8] codes of practice concerning the control of cracking occurring in RC tank walls with the use of a simplified method is verified. A special focus is given to the control of cracking induced by thermal effects. Moreover, the paper presents vital issues not mentioned in PN-EN 1992-3[8], i.e. the influence of concrete cover thickness, concreting conditions and non-uniform self-equilibrating stresses. It proposes relationships and corrective values, with the use of which values φs and sz, appropriate for cases other than those defined in PN-EN 1992-3[8], can be established. It is shown that code charts 7.103N and 7.104N concerning φs* and sz*, due to code assumptions, have a very limited range of practical use.
Abstract:The conducted investigation focused on sorting Polish pine sawn timber with regard to strength, using the visual method in accordance with the PN-D-94021 standard [4]. The sawn timber was obtained from four selected Poland’s nature and forest lands: Land A – MazovianPodlasian Nature and Forest Land (Forest District Garwolin), Land B – Little Poland Nature and Forest Land (Forest District Przedbórz), Land C – Silesian Nature and Forest Land (Forest District Kedzierzyn Koźle), Land D – Carpathian Nature and Forest Land (Forest District Piwniczna).
Abstract:The paper summarises the existing results of the authors’ own research in the range of design of lap-joints with blind fasteners Huck BOM of cold-formed steel profiles. Formulae for their resistance and stiffness have been proposed with reference to the Eurocode EC3. Investigations are part of the research, which aims to develop the structural system of lightweight steel halls. The aim of this article is a comprehensive presentation of basic issues related to the design of bar structures with such connections.
Abstract:Prestressed concrete was used to raise building constructions in Poland at the beginning of 1950s. Firstly, large span post-tensioned roof girders were made in industry halls, warehouses, airport hangars ....and so on, and also they were used to construct large capacity liquid tanks and bridges. The new form of post-tensioning, which means unbonded tendons, was used in buildings after 2000. Lately, the first time in Poland, prestressing has been used in project of two churches. As a result of using the unbonded tendons attractive forms were received. The slender prestressed slab supported on the steel “sapling” was constructed in the first of them. A prestressed concrete circumferential ring allows to create a delicate structure of timber girders in the second church. In this paper, these solutions are presented in detail together with the obtained benefits and proper calculation results.
Abstract:This paper summarises a study on the imperfection sensitivity of the shell of a steel cylindrical tank. The loadings – normal to the peripheral of the shell and along it were taken into consideration. A bifurcation analysis and then a non-linear analysis with geometric imperfections, which amounted to 2, 5, 10 mm, were conducted. Comparison of the results is given in the form of charts and tables, some conclusions are then drawn.
Abstract:A choice of studies, which is accurate and consistent with interests, is extremely important. The article presents the results of investigations relating to the motives of candidates for studies called Transportation, being realised at the Faculty of Civil Engineering of the Cracow University of Technology. The aim of the investigations was to examine this phenomenon. The investigations were executed by the method of questionnaires. They were realised among students of all years of stationary engineering studies (1st degree), that is to say I, II, III and IV year of Transportation studies. They had been preceded with several years of preliminary investigations, which showed interest of about 10–20% of the studied line by I year students. The analysis made on the basis of broadened proper investigations revealed that about 29% of students of all years that were questioned are interested in the studied line.
Ostrowski, Krzysztof, Kinasz, Roman, Cieślik, Jerzy, Wałach, Daniel
Type: Article
Release date:
2016
Abstract:This article presents the influence of carbon fibre reinforced polymer sheets (CFRP) on the strength of normal and fibre concrete columns determined in uniaxial compression. Fibre reinforced concrete (FRC) belongs to a special concrete group which is characterised by special properties without strength [12]. By using CFRP, we can modify the process of work of these composites, which are adhered to a prepared surface using a high performance resin, especially as is shown in this article. This composite material works in an elastic-plastic range with strengthening.
Abstract:The article describes dynamic analyses of frame foundation for a turbine set with a capacity of 20 MW. In the introduction, the author discusses a general method of performing dynamic calculations in building structures. The natural analyses were performed using three methods: a simplified method, a finite element method for the bar structure and the volumetric structure. The course of action was described in detail. The quality of the results was compared. General recommendations for this type of analyses were formulated.
Abstract:The history and structure of the historical covered wooden bridge built over the Osam River in the Bulgarian town of Lovech is described and discussed in detail. This bridge was completed in 1874 by Kolyu Ficheto and had a total length of approximately 86 m. The original bridge burned down in 1925. Its present structure is partially made from reinforced concrete and was opened to the traffic in 1931.
Abstract:In the second part of this article, the development of the timber bridges is shown in detail in relation to the historical and cultural contexts specific to different regions subjectively selected from around the world. For such a purpose, some iconic timber bridges are presented and discussed on a country by country basis. Their mutual comparison allows us not only to appreciate the craftsmanship of both ancient and medieval builders but also to see the diversity of the proposed structural solutions.
